Thread regulators for sewing machines



1956 E. J. CZAJKOWSKI 2,730,061

THREAD REGULATORS FOR SEWING MACHINES Filed Oct. 4. 1951 2 Sheets-Sheet 1 IN VEN TOR.

AT TURN E Y Jan. 10, 1956 Filed Oct. 4, 1951 E. J. CZAJ KOWSKI THREAD REGULATORS FOR SEWING MACHINES WITNESS 2 Sheets-Sheet 2 IN VEN TOR.

ATTORNEY United States Patent THREAD REGULATORS FGR SEWING MACHINES Edward J. Czajkowski, Lynchburg, Va., assignor to The Singer Manufacturing Company, Elizabeth, N. J., a corporation of New Jersey Application October 4, 1951, Serial No. 249,737

10 Claims. (Cl. 112-254) The present invention relates to a thread regulator for a multi-thread sewing machine, and more particularly for an overedge sewing machine of the hosiery seaming type.

In hosiery seaming it is essential to produce a uniform seam that is neat and attractive. In nylon stockings, the seam is usually three-thread chain-stitch and in order to obtain uniformity it is desirable that the amount of each of the three threads used in each stitch be definitely proportioned with respect to one another, which proportion must be maintained throughout. It is a more specific object of the present invention to provide such a thread regulator that will definitely proportion the desired amount of each of the threads necessary to produce a neat and attractive seam, and one which will maintain the desired setting to produce a uniform seam.

A further object of the present invention is to provide a means for readily adjusting the thread tension of a multi-thread machine to compensate for changes in humidity or in the desired tightness of seam formation.

Having in mind these and other objects that will be evident from an understanding of this disclosure, a presently preferred embodiment of the invention is hereinafter set forth in such detail as to enable those skilled in the art to readily understand the function, operation, construction and advantages of it, when read in conjunction with the accompanying drawings in which: t

Fig. 1 is a side elevational view of a hosiery seaming machine having a thread regulator secured thereto and made in accordance with the present invention.

Fig. 2 is an exploded perspective view of the thread tension element shown in Fig. 1 which is common to all three threads.

' Fig. 3 is a fragmentary top plan view, partly broken away, of the sewing machine illustrated in Fig. 1.

Fig. 4 is a perspective view of the novel thread regulator device included in Fig. 1 and shown per se.

The hosiery seaming machine illustrated inthe accompanying drawings is substantially the same as that disclosed in the U. S. patent of Hacklander, No. 2,277,970, March 31, 1942, and it is therefore deemed necessary only briefly to describe herein the mechanism thereof, i. e., suflicient to illustrate the manner in which the thread regulator is intended to be used and applied to the machine, and the function of it.

As illustrated in the accompanying drawings, the machine includes a frame 1 having a standard 2 and a laterally projecting overhanging bracket 3. Supported by the standard 2 is an inner feed-cup 4 which cooperates with an outer feed cup 5 depending from the overhanging bracket 3. The actuation and operation of the feed mechanism. are fully set forth in the US. patent of Hacklander, No. 2,277,971 and its above-mentioned companion patent, No. 2,277,970. As is common in machines of this type, the feed-cups 4 and 5 support and feed the fabric sections past the stitch-forming devices at auniform rate. a The feed mechanism derives its motion from a mainshaftfi projecting transversely through the standard 2 and carrying at each end a balance-wheel 7, one of which is shown in Fig. 1, which balance wheels have belt grooves formed integral therewith in the usual manner, and one of the balance wheels disposed to receive a belt for driving the machine. A needle-bar 8 carrying an eye-pointed needle 9 upon the outer end thereof is mounted in the standard 2 for reciprocation in a horizontal plane by the main-shaft 6 through appropriate connections. Adapted to cooperate with the needle in the formation of a threethread overedge chain-stitch is a primary looper 10 and a secondary looper 11, both of the threaded type. The primary looper 10 is secured to and depends from a looper-carrier 12 which is secured upon the outer end of a short horizontal shaft 13 journaled, in an angular relation to the needle-bar 8, in the lower portion of a bracket 14 depending from the overhanging bracket 3 of the machine frame 1. At the inner end of the shaft 13 is a downwardly extending rock-arm 15, the lower end of which is connected through a ball-and-socket joint with one end of a link 16 connected at its other end through a ball-and-socltet joint to a bracket 17 secured to the needlebar 8. The looper 10 thus derives its motion from the needle-bar 8.

The secondary looper 11 is secured to the upper end of a short vertically inclined shaft 18, located in a vertical plane substantially at right angles to the longitudinal axis of the needle-bar 8, and journaled for oscillation in spaced bearing lugs 19 and 20 formed integral with the machine frame 1. The shaft 18, and hence the looper 11, is actuated from the main-shaft 6 by suitable connections including an upwardly and rearwardly inclined rockarm 21. Reference is made to the above-mentioned patents of Hacklander Nos. 2,277,970 and 2,277,971 for a complete disclosure of the details of the actuating mechanisms of the machine.

The thread regulator, constructed in accordance with the present invention, includes a carrying-plate 22 adapted to be secured to the left side of the frame 1 near the upper portion thereof, as seen in Fig. 1, by means of bolts 23, adapted to pass through apertures 24 therein, and to be screwed into the frame 1. Spacers 25, in the form of cylinders, are interposed between the frame 1 and the plate 22 to provide a clearance therebetween. The plate 1 is held substantially in a vertical plane parallel to a vertical plane including the center line of the machine.

Four bars 26 are secured to the plate 22 by means of screws 27 which pass through apertures in the plate and which are screwed into threaded axial holes in the end of the bars, the heads of the screws lying in the clearance between the plate 22 and frame 1. The bars 26 are positioned normal to the plate 22 and are arranged in a stag gered relationship with respect to each other. Slidably carried by the bars 26 are rods 28, adapted to be secured in vertically adjusted position by screws 29 which are made readily accessible by the staggered relation of the bars 26 and by arranging the screws outwardly of the bars 26, i. e., the screws on the two bars to the left as seen in Figs. 1 and 3 are on the left sides thereof, and those on the two bars to the right are on the right sides thereof. Three rods 28 are provided on each of the bars 26, and as seen in Fig. 3, the corresponding rods 28 on each of the bars 26 lie substantially in a single vertical plane. Thread apertures 30 are provided adjacent the ends of each of the rods 28, those apertures in the rods in the two uppermost disposed bars 26, i. e., the sets of rods which appear first and third from the right in Figs. 1 and 3, are located at the lower extremities of the rods, and those apertures in the other two sets of rods are located at the upper extremities. The thread apertures in the rods 28 are staggered from a horizontal plane.

Secured to the plate 22 is a tension-disk supporting bolt 31, of'which the inner end is reduced to form a 3 neck 32-(Fig. 3) thatprojects through aspacer 33 and the plate 22, which neck is upset at its end to lock the spacer 33 and plate 22 between the shoulder at the beginning of the :neck and the'upset-end, thus securi-ngthe bolt 31 to the plate wi-ththe bolt:a-rranged normal thereto. The free or outer end of the bolt 31:is threaded, as at34, and intermediatezthe ends it is provided with the usual thread grooves 35'. Slidably' mounted upon the bolt 31arethree pairs :of thread tension :discs 36,-separated by spacers '37 sorthatthe meeting faces between the discs of each pair willlie substantially in a vertical plane including the respective thread groove 35. Thediscs 36 are resiliently urged; together by-aspring 38 provided with. end caps 39, all of which encircle the bolt 31. The spring '38 is placed undercompressionby means of nut 40 screwed upon the threaded-endofthe bolt '31 and locked in the desired position by;a.lock=nut 41. Toprevent rotation of the tension dises 3.6on.,the bolt 31, and thus insure frictional resistance 7 tomovement of the thread inserted between the respective pilirsncach of the discs36 isyformed with acut-out portion 42 atzthe periphery thereof, whichcut-out portions are engaged by a stop-rod 43 secured to theplate 22 at one end and projecting normal therefrom, parallel to the bolt 31.

Abracket 44 consisting of a vertical leg 45 and a horizontal leg 46 formedat right angles to each other is secured to the plate 22 by means of a screw 47 passing through the vertical leg45. The bracket is arranged on the ,plate so that the horizontal leg 46 will overhangthe tensiqndiscs 36. Thread guides comprising grommeted apertures 48'formed in thehorizontal leg 46 of the bracket 44; are vertically aligned with the respective pairs of tension discs 36. Additional thread handling devices include a wireguide 49 bent to form a thread eye at one end and a securing eye at the other depending from the screw 23, a similar .wire guide 50 secured to the endof the shaft 13 by ,an axial screw 51, a third wire guide 52secured to the side standard 2 of theframe 1 by means of a screw 53, an arm 54 having two thread eyes formed therein dependingfrom the overhanging bracket 3, a thread controller 55 Secured ,tothe shaft 18, and twoeyes consisting of sleeves 5 6 projecting through apertures formed in the depending bracket14.

It will be noted that the thread tensioning and guiding devices carried by the plate 22 are arranged in three series, each containing an eyelet 48 in the leg 46, a cooperating pair of thread tension disks 36,.a thread groove 35 in the bolt 31, and a correspondingone of the rods 28 on each of the four bars 26. The elements of each series lie substantially in a vertical plane parallel to a vertical plane including the center line of the machine. Upon running a thread through each of the series of devices, it is first led in from a source of supply, down through the eyelet 48, between the cooperating tension disks 36, into the thread grooves 35, and through the eyes 30 of the rods 28.

Asshown in the drawings,.a needle thread 57 is threaded through the first series of devices, i. e., the series nearest the machine frame. from the regulator, thethread passes through the bent wire guide 49, through the upper eye of the two. in the depending guide54, through the eye of the bent wire guide 52, to the control element 55,.through the lower of the two eyelets in the depending guide 54, and to'the eye of the needle. The primary looper thread 58 is-threaded through the second or middle series of devices in the regulator, and passes therefrom through the eye of the bent wire guide '50 and through one of the eyelets 56in the depending bracket 14 to the eye of the looper. The secondary looper thread 59 is threaded through the third or outermost series of devices in the regulator, andpasses therefrom through the eye of the bent wire guide 50 and through the other of the eyelets 56 in the depending bracket 14 to the eye of the looper.

It will be seen that the thread regulator which is illustrated as used on a three-thread hosiery seaming machine includesa common tension for all the threads and an individual tension for each of the threads. The individual thread tension means consist of the vertically-adjustable rods which cause the threads to follow a sinuous path in passing through the eyes thereof because of the staggered relation of them. As will be readily understood, the sinuous travel of the thread gives rise to resistance to movement. By varying the vertical adjustment of the rods 28, the sinuosity of the individual paths can-be increased or decreased, thus varying the resistance to movement of the individual thread therethrough. To obtain the desired proportion of each thread, the resistances to the'passages of the threads are'varied inversely with :amount desired, i. e., if a larger proportion of one thread is desired, the sinuosity of its path is reduced, or if. a smaller proportion is desired, the sinuosity of its path is increased.

By means of the common-tension, which is comprised of the disks 36, the tension upon all the threads can be simultaneously increased or decreased by varying the position of the nut 40' and consequently varying the compression of the spring 38. It will be understood that the resistance imposed by the common tension -on-the=individual threads is substantially equal on each andany change in the tension will affect the threads equally. Thus, whenever, it is necessary to vary the tensionof the threads due to a change in the humidity or desired tightness of seam formation, it can be readily accomplished by adjusting the tension of the spring 38 on the common tension device. Normally, after having once determined the desired setting of the rods 28 for the particular type of stitch employed, no further adjustments of the rods 23 are necessary except to compensate for slight amounts that it came out'of alignment, since all necessary adjustments can be done'by the common tension.

Numerous alterations of the structure herein disclosed will suggest themselves to those skilled in the art. However, -it is to be understood that the present disclosure relates to a preferred embodiment of my invention which is for purposes of illustration only and notto be construed as a'limitation thereof. All such modifications which do not depart from the spirit of my invention areintended to be included within the scope of the appended claims.

Having thus described my invention, what I claim herein is: a

1. Thread regulating means for a multi-thread sewing machine comprising a plate adapted to be secured to the frame of the machine, a plurality of bars extending from the plate, aplurality of rods carried by the bars, each of which rods isprovided with a thread guide, one of said rods being 'provided'on each of said bars for each of the threads in the stitch structure and the correspondingrods on each of he bars constituting a series, said rods beingv adjustable with respect to the bars to stagger the thread guides ofthe rods in each series and to vary theistaggered relation thereof, whereby the threads traversing .each series of thread guides will follow tortuous paths, which paths can be individually varied to increase or decrease tnetension imposed'upon them.

2. Thread regulating means for a multi-threadsewing machine comprising a plurality of substantially parallel bars, a plurality of rods carried by thebars, .each of which rods is provided with a thread guide, one of saidrods being provided on each. of said barsfor each of the-threads in the stitch structure and the corresponding rods-on each of the bars constituting a series, said-rods being adjustable with respect to the bars to stagger the thread guides ofv the rods in each series and to vary the staggered'relati'on' thereof, whereby the threads traversing each series of thread guides will follow tortuous paths, which paths can be individually varied to increase ordecrease the tension imposed upon them.

3. In a sewing machine for forming a multi-threa'd stitch structure, a thread 'regulating'mea'n's 'forproportiom ing the amount of each thread in the stitch 'structurcy 5 an equal tension on each of the threads, means for adjusting said first tension means to simultaneously vary the tension imposed thereby upon each of the threads an equal amount, and a second tension means for placing an individually adjustable tension on each of the threads independent of said first tension means.

4. In a sewing machine for forming a multi-thread stitch structure, a thread regulating means for proportioning the amount of each thread in the stitch structure, said regulating means comprising a first tension means including a bolt, a cooperating pair of tension disks on the bolt for each thread in the stitch structure, a spring surrounding the bolt for resiliently urging all the tension disks simultaneously into abutment with its cooperating disk, and a nut threaded upon the bolt by means of which the tension of the spring can be varied, and a second tension means for placing an additional tension independent of said first tension means upon each of the threads, said second tension means being individually adjustable with respect to each of the threads.

5. In a sewing machine for forming a multi-thread stitch structure, a thread regulating means for proportioning the amount of each thread in the stitch structure, said regulating means comprising a first tension means including a bolt, a cooperating pair of tension disks on the bolt for each thread in the stitch structure, a spring surrounding the bolt for resiliently urging all the tension disks simultaneously into abutment with its cooperating disk, and a nut threaded upon the bolt by means of which the tension of the spring can be varied, and a second tension means for placing an additional tension upon each of the threads, said second tension means subjecting each of the threads to an individual tortuous path of travel therethrougn, said paths of travel being individually adjustable to vary the tension imposed upon each thread.

6. Thread regulating means for a multi-thread sewing machine comprising a first tension means including a bolt, a cooperating pair of tension disks on the bolt for each thread in the stitch structure, a spring surrounding the bolt for resiliently urging all the tension disks simultaneously into abutment with its cooperating disk, and a nut threaded upon the bolt by means of which the tension of the spring can be varied, a second tension means for individually tensioning each thread independently of the first tension means and for individually adjusting the tension thereby imposed, said second tension means comprising bars lying substantially parallel to said bolt, a rod for each of the threads slidably carried by each of the bars and each rod provided with a thread eye, said rods being adjustable to stagger the thread eyes thereon and to vary the staggered relationship thereof, whereby the threads passing through the thread eyes will follow tortuous paths, which paths can be varied to increase or decrease the thread tensions.

7. Thread regulating means for a multi-thread sewing machine comprising a first tension means including a bolt, a cooperating pair of tension disks on the bolt for each thread in the stitch structure, a spring surrounding the bolt for resiliently urging all the tension disks simultaneously into abutment with its cooperating disk, and a nut threaded upon the bolt by means of which the tension of the spring can be varied, a second tension means for individually tensioning each thread independently of the first tension means and for individually adjusting the tension thereby imposed, said second tension means com prising a plurality of bars lying substantially parallel to said bolt, a plurality of rods each having a thread guide arranged upon said bars, one of said rods being provided for each thread on each bar and the corresponding rods upon each bar constituting a series, said rods being adjustable to stagger the thread eyes of the rods in each series and to vary the staggered relation thereof, whereby the threadspassing through each series of thread guides will follow tortuous paths, which paths can be individually varied to increase or decrease the thread tensions.

8. Thread tensioning means for a sewing machine comprising a plurality of rods each of which is provided with a thread guide, said rods being arranged substantially in a plane with the axes of the thread guides located substantially parallel to the plane defined by said rods for the passage of a thread successively through said thread guides, said rods being longitudinally adjustable relative to each other to stagger the thread guides and to vary the staggered relation thereof, whereby the thread traversing the thread guides will follow a tortuous path that can be selectively varied to increase or decrease the tension imposed upon the thread.

9. A sewing machine having a plurality of stitchtorming instrumentalities including a needle and a looper, a thread provided for each of said instrumentalities, said instrumentalities cooperating during operation of said machine to form a multi-thread stitch structure, a thread regulating means for proportioning the amount of the needle and looper threads consumed in the stitch structure, said regulating means comprising a first tension means common to all threads in the stitch structure and placing an equal tension on each of the threads, means for adjusting said first tension means to srnultaneously vary the tension imposed thereby upon each of the threads an equal amount, and a second tension means for placing an in dividually adjustable tension on each of the threads independent of said first tension means.

10. A sewing machine having a needle and a plurality of loopers, each of said needle and loopers having a thread receiving aperture adjacent the points thereof, threads provided for each of said needle and loopers and being threaded through said apertures, said needle and loopers being designed to cooperate during operation of the machine to form a multi-thread chain-stitch structure, and a thread regulating means for proportioning the amount of each thread in the stitch structure, said regulating means comprising a first tension means common to all threads in the stitch structure and placing an equal tension on each of the threads, means for adjusting said first tension means to simultaneously vary the tension imposed thereby upon each of the threads an equal amount, and a second tension means for placing an individually adjustable tension on each of the threads independent of said first tension means.

References (Iited in the file of this patent UNITED STATES PATENTS 1,020,090 Gray Mar. 12, 1912 l,04l,574 Burton Oct. 15, 1912 1,151,513 De Voe Aug. 24, 1915 1,519,486 Clayton Dec. 16, 1924 

